t5743n ATMEL Corporation, t5743n Datasheet - Page 22

• Manufacturer Part Number: t5743n
• Description: Ask/fsk Receiver
• Manufacturer: ATMEL Corporation

The configuration registers are programmed serially via
the bi-directional data line according to figure 33 and fig-
ure 34.
To start programming, the serial data line DATA is pulled
to Low for the time period t1 by the µC. When DATA has
been released, the receiver becomes the master device.
When the programming delay period t2 has elapsed, it
emits 15 subsequent synchronization pulses with the
pulse length t3. After each of these pulses, a programming
window occurs. The delay until the program window
starts is determined by t4, the duration is defined by t5.
Within the programming window, the individual bits are
set. If the µC pulls down Pin DATA for the time period t7
during t5, the according bit is set to ’0’. If no program-
ming pulse t7 is issued, this bit is set to ’1’. All 15 bits are
T5743N
Serial bi–directional
data line
Out1 (
Data_out (DATA)
IC_ACTIVE
22 (34)
V S = 4.5 V to 5.5 V
Data_In
Data_out
X
X
Receiving
mode
0 V / 5 V
t1
Interface
Input –
t2
Preliminary Information
Figure 33. Timing of the register programming
T5743N
t3
(Start bit)
t4
Bit 1
(”0”)
0 ... 20 V
t5
t7
Figure 34. Data interface
t6
DATA
Programming frame
(Register–
Bit 2
(”1”)
select)
subsequently programmed this way. The time frame to
program a bit is defined by t6.
Bit 15 is followed by the equivalent time window t9. Dur-
ing this window, the equivalence acknowledge pulse t8
(E_Ack) occurs if the just programmed mode word is
equivalent to the mode word that was already stored in
that register. E_Ack should be used to verify that the
mode word was correctly transferred to the register. The
register must be programmed twice in that case.
Programming of a register is possible both in sleep– and
in active–mode of the receiver.
During programming, the LNA, LO, lowpass filter IF-
amplifier and the FSK/ASK Manchester demodulator are
disabled.
V
R
Serial bi–directional data line
C
pup
X
L
= 5 V to 20 V
(Poll8)
Bit 14
(”0”)
I/O
µC
(Stop bit)
Bit 15
(”0”)
Out1 µC
Rev. A1, 25-May-00
t8
t9
T Sleep T Start–up
Sleep
mode
Start–up
mode